• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.599-602
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• 2006

본 논문에서는 변형된 QMSA에 전기력선이 제한되지 않도록 용량을 장하한 MSA를 제안 하였다. 안테나의 크기는 약 $30mm\times86.6mm\times1.575mm$의 크기를 갖는다. 안테나 특성은 듀얼밴드 설계에서 1.93GHz와 2.03GHz의 두 동작 주파수 동조를 수월하게 하였다. 듀얼밴드 동작을 얻기 위한 기술은 양측 평행 평판과 $\lambda/2$ 방사 폐치를 변화시킴으로서 조정할 수 있다. 또한 1.93GHz 와 2.03GHz의 동작 주파수에 대해 E면과 H면에서 시뮬레이션 된 방사 패턴은 비교 분석되었다. 이동 통신을 위한 설계 제작된 듀얼 밴드 안테나 이득은 약 11.394dBi 이고 이득 변화는 아래와 위 공진 주파수에 대해 1.0dBi 보다 작다.

• Korean Journal of Optics and Photonics
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• v.2 no.3
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• pp.121-126
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• 1991

The knife-edge scanning type OTF measuring equipment is improved to enhance the accuracy in off-axis OTF measurement and the accuracy of this equipment of evaluated by measuring the OTF of 50 mm plano-convex standard lens developed by SIRA group. Measured MTF values of the standard lens are in good agreement with SIRA results within $\pm$0.02 on axis and % $\pm$0.03 off-axis in 0-100 clmm frequency range except only a few spatial frequencies. Measured PTF values are good agreement with SIRA results within $\pm$$5^{\circ}$.

• Food Science of Animal Resources
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• v.21 no.1
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• pp.64-70
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• 2001

The extraction procedure and HPLC condition were modified to analyze the residues of oxytetracycline, sulfamethoxazole and chloramphenicol in pork, simultaneously. The antibacterial agents in pork were extracted with 0.02M EDTA-Mcilivine buffer:ethanol:acetonitrile (5:3:2). After the removal of fat with n-hexane, the extracts were evaporated and purified with Sep-pak $C_{18}$ cartridge column using 0.01M oxalic acid 0.1% (v/v) triethylamine (TEA) in acetonitrile. The peak of antibacterial agents was detected with $\mu$ Bondapak C18 column, UV detector (280nm) and 0.01M oxalic acid: methanol: acetonitrile (7.5:2.0:0.5). Detection limits for three antibacterial standards were 0.03 ppm. Calibration curves were linear between 0.03 and 2.0 ppm (R$^2$>0.999). When spiked the level of 1.0 ppm of oxytetracycline, sulfamethoxazole and chloramphenicol into meats, the recoveries from meats were 77.3%, 79.7% and 59.3%, respectively. These results showed that the modified extraction method provided good analytical resolution and the recoveries of the above antibacterial agents in meats.

• Korean Journal of Clinical Pharmacy
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• v.10 no.2
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• pp.74-79
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• 2000

Y-Site 투여시 $5\%$포도당액과 생리식염수에서 탁솔과 은단세트론의 안정성에 관해 실온과 형광등 아래서 연구하였다. 온단세트론 0.03 mg/ml, 0.1 mg/ml, 0.3 mg/ml와 탁솔 0.3 mg/ml, 1.2mg/ml를 각각 1:1로 혼합한 후 0, 1, 2, 4, 12시간에서 즉시 약물농도를 HPLC로 분석하였다. 방해물질에 의한 분석오차를 줄이기 위해 분석법을 여러상태에서 확인하였으며, 각 농도에서 3차례씩 실험하였고 각 샘플은 2차례 연속 HPLC 분석하였다. 분석전에 각 시료의 투명도, 색의변화, 침전상태 및 pH를 검사하였다. 온단세트론 0.03, 0.1 및 0.3 mg/ml와 탁솔 0.3 및 1.2mg/ml를 각각 혼합하였을 때 12시간 동안 안정성이 있었다. 혼탁이나 색의 변화 및 침전은 나타나지 않았으며 12시간 동안 pH의 변화는 특별한 경향이 없었다.

• Bulletin of the Korean Chemical Society
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• v.22 no.12
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• pp.1341-1344
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• 2001

Comparison of sulfur dioxide primary standard gases of the Korea Research Institute of Standards and Science (KRISS, Korea) and the National Physical Laboratory (NPL, UK) was performed. 100 ${\times}$10-6 mol/mol and 1,000 ${\times}$10-6 mol /mol primary standard gases (designated NPL S115 and S114, respectively) prepared gravimetrically and validated in NPL were used as transfer standards. Transfer standards were analyzed by NDIR sulfur dioxide analyzer and compared with KRISS PSM 112-03-624 and PSM 112-03-625 prepared gravimetrically. Adsorption corrected relative deviations of the primary standard gases were agreed to within 0.1%, and this agreement is within the expanded uncertainties (k = 2) of the primary standards at the two laboratories.

• Food Engineering Progress
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• v.13 no.1
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• pp.32-37
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• 2009

Central composite design was applied for the ultrasound-assisted extraction from peel and seed of Campbell Early grapes and the extraction processes were optimized for the antiradical activities of the extracts by using response surface methodology. Optimal conditions were 53.45% of ethanol concentration, 45.99${^{\circ}C}$ of extraction temperature and 23.93 min of extraction time for the maximum antiradical activity of grape peel extract (54.98%) and 53.14% of ethanol 56.03${^{\circ}C}$ of temperature and 29.03 min of time for maximum antiradical activity of grape seed extract (90.60%).

• Bulletin of the Korean Chemical Society
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• v.14 no.2
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• pp.292-294
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• 1993

Three derivatives of poly(ethylenimine) (PEI) are prepared by Ni(II)-template condensation with glyoxal(GO): PEI[Ni(II)-GO]$_{0.08}$ (1), PEI[Ni(II)-GO]$_{0.03}$ (2), and lau$_{0.18}$PEI[Ni(II)-GO]$_{0.03}$ (3). The contents of Ni(II)-macrocyclic center of 1-3 are 8%, 3%, or 3%, respectively, of the monomer residues, and 18% of monomer residues for 3 are laurylated. The pH profiles for k$_{cal}$ and k$_m$ for the deacylation of 4-carboxy-2-nitrophenyl acetate are measured. The relative magnitude of the parameters for 1-3 and different shapes of the pH profiles for 1-3 are explained in terms of the electrostatic and the hydrophobic effects exerted by the metal centers and lauryl groups. For the artificial metalloenzymes built on PEI, therefore, the ionization of functional groups and the affinity toward counter-anions can be controlled by adjusting charge density and the content of hydrophobic groups.

• Design & Manufacturing
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• v.15 no.2
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• pp.56-62
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• 2021

In this study, design technology of a non-mechanical flow meter using fluidic oscillation generated during the fluid flow in the chamber was investigated. To with respect to design a splitter, which is the most important factor in fluid oscillation, a transient flow simulation analysis was performed for three types of shapes and changes in inlet flow velocity. The oscillation characteristics with respect to the time in each case were compared, and it was confirmed that the SM03 model was the best among the presented models. In addition, the FFT analysis of the fluid oscillation results for the SM03 model was used to obtain a linear correlation between the flow velocity change and the maximum frequency, and a frequency of 20.957 (Hz/m/s) per unit flow velocity was obtained. Finally, injection molding simulation and molding experiment of the chamber with the designed splitter were performed.

• Journal of information and communication convergence engineering
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• v.19 no.1
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• pp.61-66
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• 2021

An underwater remotely operated vehicle (ROV) has been implemented. It can inspect foreign substances through a CCD camera while the ROV is running in water. The maximum thrust of the ROV's running thruster is 139.3 N, allowing the ROV to move forward and backward at a running speed of 1.03 m/s underwater. The structural strength of the guard frame was analyzed when the ROV collided with a wall while traveling at a speed of 1.03 m/s underwater, and found to be safe. The maximum running speed of the ROV is 1.08 m/s and the working speed is 0.2 m/s in a 5.8-m deep-water wave pool, which satisfies the target performance. As the ROV traveled underwater at a speed of 0.2 m/s, the inspection camera was able to read characters that were 3 mm in width at a depth of 1.5 m, which meant it could sufficiently identify foreign objects in the water.

• Nonlinear Functional Analysis and Applications
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• v.26 no.3
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• pp.475-496
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• 2021

The main aim is to define a new class of generalized h-variational inequality problems and its generalized h-variational inequality problems. We define the class of h-𝜂-invex set, h-𝜂-invex function and H-pseudospace. Existence of the solution of the problems are established in H-pseudospace with the help of H-KKM mapping theorem and HC_*-condition of 𝜂 associated with the function h.